Turbine nozzle having an angled inner band flange

BACKGROUND OF THE INVENTION

0001The field of the disclosure relates generally to rotary machines, and more particularly, to an inner band of a turbine nozzle that includes an obliquely oriented portion.

0002At least some known rotary machines include a compressor, a combustor coupled downstream from the compressor, a turbine coupled downstream from the combustor, and a rotor shaft rotatably coupled between the compressor and the turbine. Some known turbines include at least one rotor disk coupled to the rotor shaft, and a plurality of circumferentially-spaced turbine blades that extend outward from each rotor disk to define half of a stage of the turbine. The other half of the turbine stage includes a row of stationary, circumferentially-spaced turbine nozzles axially positioned between adjacent rows of turbine blades. Each turbine nozzle includes an airfoil that extends radially outward from an inner band towards a turbine casing.

0003At least some known turbine nozzles include an inner band that includes an axially-extending platform portion and a radially-extending flange portion. The airfoil is coupled to the platform portion and the flange portion couples the turbine nozzles to retaining rings within the turbine. In at least some known turbine engines, the position of the flange portion is determined by the configuration of the retaining ring and how the retaining ring attaches to the turbine nozzle. As such, in at least some known turbine engines, the flange portion of the inner band is not axially aligned with the throat location of the turbine nozzle due to space limitations within the turbine.

0004Furthermore, in some known configurations, the flange portion is radially oriented and both the platform portion and the flange portion include slots defined therein that receive a strip seal. Such designs may not satisfy positive back flow margin design specifications due to increased leakage areas at the intersection of the strip seals in the platform portion and flange portion.

BRIEF DESCRIPTION

0005In one aspect, an inner band assembly for a turbine nozzle of a rotary machine that includes a centerline axis is provided. The inner band assembly includes a platform portion and a first flange coupled to the platform portion. The first flange is obliquely oriented with respect to the centerline axis. The inner band assembly also includes a second flange coupled to the first flange. The second flange is obliquely oriented with respect to the first flange.

0006In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the platform portion and the first flange intersect at a point that is axially aligned with a throat location that is at least partially defined by the turbine nozzle.

0007In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the platform portion extends in a substantially axial direction, and wherein the second flange extends in a substantially radial direction.

0008In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the first flange is obliquely oriented with respect to the platform portion.

0009In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the first flange includes a first end coupled to the platform portion, a second end coupled to the second flange, and a forward surface extending between the first end and the second end. The first flange also includes an aft surface extending between the first end and the second end, wherein the forward surface and the aft surface define a thickness therebetween that is constant between the first end and the second end.

0010In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the platform portion includes a platform seal slot including a first end and a second end. The first flange includes flange seal slot that intersects the platform seal slot, wherein the flange seal slot is obliquely oriented with respect to the platform seal slot.

0011In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the flange seal slot intersects the platform seal slot at a throat location at least partially defined by the turbine nozzle.

0012In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the flange seal slot extends into the second flange.

0013In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the second flange includes a forward surface, and wherein the flange seal slot is at least partially defined in the forward surface.

0014In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the second flange is oriented perpendicular to the centerline axis.

0015In another aspect, a turbine nozzle for a rotary machine including a centerline axis is provided. The turbine nozzle includes an airfoil including a leading edge and a trailing edge. The airfoil defines a throat location proximate the trailing edge. The turbine nozzle also includes an inner band assembly including a platform portion coupled to the airfoil, and a first flange coupled to the platform portion. The first flange is obliquely oriented with respect to the platform portion, and the platform portion and the first flange intersect at a point axially aligned with the throat location.

0016In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the first flange is obliquely oriented with respect to the centerline axis.

0017In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, a second flange is coupled to the first flange, wherein the second flange is obliquely oriented with respect to the first flange.

0018In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the platform portion extends in a substantially axial direction, and wherein the second flange extends in a substantially radial direction.

0019In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the first flange is positioned radially inward of the platform portion and wherein the second flange is positioned radially inward of the first flange.

0020In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, the second flange is axially offset from the throat location.

0021In another aspect, a method of manufacturing a turbine nozzle for a rotary machine including a centerline axis is provided. The method includes coupling an airfoil to a platform portion of an inner band assembly and coupling a first flange of the inner band assembly to the platform portion such that the first flange is obliquely oriented with respect to the centerline axis. The method also includes coupling a second flange of the inner band assembly to the first flange such that the second flange is obliquely oriented with respect to the first flange.

0022In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, coupling the first flange to the platform portion includes coupling the first flange to the platform portion such that the first flange and the platform portion intersect at a throat location at least partially defined by the airfoil.

0023In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, coupling the airfoil to the platform portion includes coupling the airfoil to the platform portion such that the platform portion extends in a substantially axial direction. Furthermore, coupling the second flange to the first flange includes coupling the second flange to the first flange such that the second flange extends in a substantially radial direction.

0024In one aspect of the disclosure, which may include at least a portion of the subject matter of any of the preceding and/or following examples and aspects, coupling the first flange to the platform portion includes coupling the first flange to the platform portion such that the first flange is obliquely oriented with respect to the platform portion.

BRIEF DESCRIPTION OF THE DRAWINGS

0025These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

0026<figref idref="DRAWINGS">FIG. 1</figref> is a schematic view of an exemplary rotary machine;

0027<figref idref="DRAWINGS">FIG. 2</figref> is a partial sectional view of a portion of an exemplary high-pressure turbine assembly that may be used with the rotary machine shown in <figref idref="DRAWINGS">FIG. 1</figref>;

0028<figref idref="DRAWINGS">FIG. 3</figref> is a perspective view of an exemplary turbine nozzle that may be used with the high-pressure turbine assembly shown in <figref idref="DRAWINGS">FIG. 2</figref>;

0029<figref idref="DRAWINGS">FIG. 4</figref> is a perspective view of an exemplary inner band that may be used with the turbine nozzle shown in <figref idref="DRAWINGS">FIG. 3</figref>;

0030<figref idref="DRAWINGS">FIG. 5</figref> is a schematic view of the turbine nozzle that may be used with the high-pressure turbine assembly shown in <figref idref="DRAWINGS">FIG. 2</figref>; and

0031<figref idref="DRAWINGS">FIG. 6</figref> is a schematic view of an alternative inner band that may be used with the turbine nozzle shown in <figref idref="DRAWINGS">FIG. 3</figref>.

0032Unless otherwise indicated, the drawings provided herein are meant to illustrate features of embodiments of the disclosure. These features are believed to be applicable in a wide variety of systems comprising one or more embodiments of the disclosure. As such, the drawings are not meant to include all conventional features known by those of ordinary skill in the art to be required for the practice of the embodiments disclosed herein.

DETAILED DESCRIPTION OF THE INVENTION

0033Embodiments of the present disclosure relate to a turbine nozzle for a rotary machine having an angled flange at least partially aligned with a throat of the turbine nozzle. More specifically, the turbine nozzle includes an airfoil that defines a throat location proximate a trailing edge. The turbine nozzle also includes an inner band assembly including a platform portion coupled to the airfoil, and a first flange coupled to the platform portion. The first flange is obliquely oriented with respect to the platform portion, and the platform portion and the first flange intersect at a point axially aligned with the throat location. The inner band assembly also includes a second flange coupled to the first flange such that the second flange is obliquely oriented with respect to the first flange. The design features include positioning an intersection of the platform portion and the first flange at the throat location while also offsetting the second flange from the throat location. Such a configuration may be used in smaller sized rotary machines where spaced for the inner band assembly is limited. Furthermore, the slanted first flange creates a pressurization area inward of the platform portion that maintains a positive backflow margin up to the throat location. More specifically, axial alignment of a high static pressure area and the pressurization area forward of the first flange reduces or prevents purge air from leaking across platform portions of adjacent turbine nozzles and intermixing with the hot combustion gases in the combustion gas path.

0034In the following specification and the claims, reference will be made to a number of terms, which shall be defined to have the following meanings.

0035The singular forms “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise.

0036“Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not.

0037Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about”, “approximately”, and “substantially”, are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Here and throughout the specification and claims, range limitations may be combined and/or interchanged. Such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise.

0038As used herein, the terms “axial” and “axially” refer to directions and orientations that extend substantially parallel to a centerline of the turbine engine. Moreover, the terms “radial” and “radially” refer to directions and orientations that extend substantially perpendicular to the centerline of the turbine engine. In addition, as used herein, the terms “circumferential” and “circumferentially” refer to directions and orientations that extend arcuately about the centerline of the turbine engine. As used herein, the terms “oblique” and “obliquely” refer to orientations that extend in both non-parallel and non-perpendicular directions from a respective component or surface. More specifically, “oblique” and “obliquely” refer to an angle of orientation between two components or surfaces that is not 0 degrees, 90 degrees, or 180 degrees.

0039Additionally, unless otherwise indicated, the terms “first,” “second,” etc. are used herein merely as labels, and are not intended to impose ordinal, positional, or hierarchical requirements on the items to which these terms refer. Moreover, reference to, for example, a “second” item does not require or preclude the existence of, for example, a “first” or lower-numbered item or a “third” or higher-numbered item. As used herein, the term “upstream” refers to a forward or inlet end of a gas turbine engine, and the term “downstream” refers to an aft or nozzle end of the gas turbine engine.

0040<figref idref="DRAWINGS">FIG. 1</figref> is a schematic view of an exemplary rotary machine <b>10</b>, i.e., a turbomachine, and more specifically a turbine engine. In the exemplary embodiment, rotary machine <b>10</b> is a gas turbine engine. Alternatively, rotary machine <b>10</b> may be any other turbine engine and/or rotary machine, including, without limitation, a steam turbine engine, a gas turbofan aircraft engine, or another aircraft engine. In the exemplary embodiment, rotary machine <b>10</b> includes a fan assembly <b>12</b>, a low-pressure or booster compressor assembly <b>14</b>, a high-pressure compressor assembly <b>16</b>, and a combustor assembly <b>18</b>. Fan assembly <b>12</b>, booster compressor assembly <b>14</b>, high-pressure compressor assembly <b>16</b>, and combustor assembly <b>18</b> are coupled in flow communication. Rotary machine <b>10</b> also includes a high-pressure turbine assembly <b>20</b> coupled in flow communication with combustor assembly <b>18</b> and a low-pressure turbine assembly <b>22</b>. Fan assembly <b>12</b> includes an array of fan blades <b>24</b> extending radially outward from a rotor disk <b>26</b> toward a nacelle <b>27</b> that includes a fan case <b>29</b>. A turbine case <b>31</b> extends circumferentially around low-pressure or booster compressor assembly <b>14</b>, high-pressure compressor assembly <b>16</b>, combustor assembly <b>18</b>, high-pressure turbine assembly <b>20</b>, and low-pressure turbine assembly <b>22</b>. Rotary machine <b>10</b> also includes an outlet guide vane <b>33</b> positioned aft of fan assembly <b>12</b> and extending from turbine case <b>31</b> to fan case <b>29</b>. Low-pressure turbine assembly <b>22</b> is coupled to fan assembly <b>12</b> and booster compressor assembly <b>14</b> through a first drive shaft <b>28</b>, and high-pressure turbine assembly <b>20</b> is coupled to high-pressure compressor assembly <b>16</b> through a second drive shaft <b>30</b>. Rotary machine <b>10</b> includes an intake <b>32</b>, an exhaust <b>34</b>, and a centerline axis <b>36</b> about which fan assembly <b>12</b>, booster compressor assembly <b>14</b>, high-pressure compressor assembly <b>16</b>, and turbine assemblies <b>20</b> and <b>22</b> rotate.

0041In operation, air entering rotary machine <b>10</b> through intake <b>32</b> is channeled through fan assembly <b>12</b> towards booster compressor assembly <b>14</b>. Compressed air is discharged from booster compressor assembly <b>14</b> towards high-pressure compressor assembly <b>16</b>. Highly compressed air is channeled from high-pressure compressor assembly <b>16</b> towards combustor assembly <b>18</b>, mixed with fuel, and the mixture is combusted within combustor assembly <b>18</b>. High temperature combustion gas generated by combustor assembly <b>18</b> is channeled towards turbine assemblies <b>20</b> and <b>22</b>. Combustion gas is subsequently discharged from rotary machine <b>10</b> via exhaust <b>34</b>.

0042<figref idref="DRAWINGS">FIG. 2</figref> is a partial sectional view of a portion of high-pressure turbine assembly <b>20</b>. In the exemplary embodiment, high-pressure turbine assembly <b>20</b> includes a plurality of stages <b>100</b> that each include a stationary row <b>102</b> of a plurality of circumferentially-spaced stator vanes or turbine nozzles <b>104</b> and a corresponding row <b>106</b> of a plurality of circumferentially-spaced rotating turbine blades <b>108</b>. Turbine nozzles <b>104</b> in each row <b>102</b> are spaced-circumferentially about, and each extends radially outward from, a retaining ring <b>110</b> that is coupled between a corresponding turbine nozzle <b>104</b> and a stationary component of high-pressure turbine assembly <b>20</b>. More specifically, each turbine nozzle <b>104</b> includes an inner band <b>114</b> that is coupled to a respective retaining ring <b>110</b>. Each turbine blade <b>108</b> is coupled to a radially inner rotor disk <b>112</b>, which is coupled to second drive shaft <b>30</b> and rotates about centerline axis <b>36</b> that is defined by second drive shaft <b>30</b>. A turbine casing <b>116</b> extends circumferentially about turbine nozzles <b>104</b> and turbine blades <b>108</b>. Turbine nozzles <b>104</b> are each coupled to turbine casing <b>116</b> and each extends radially inward from turbine casing <b>116</b> towards second drive shaft <b>30</b>. A combustion gas path <b>118</b> is defined between turbine casing <b>116</b> and each rotor disk <b>112</b>. Each row <b>106</b> and <b>102</b> of turbine blades <b>108</b> and turbine nozzles <b>104</b> extends at least partially through a portion of combustion gas path <b>118</b>. In operation, the combustion gases are channeled along combustion gas path <b>118</b> and impinge upon turbine blades <b>108</b> and turbine nozzles <b>104</b> to facilitate imparting a rotational force on high-pressure turbine assembly <b>20</b>.

0043<figref idref="DRAWINGS">FIG. 3</figref> is a perspective view of turbine nozzle <b>104</b> that may be used with high-pressure turbine assembly <b>20</b> (shown in <figref idref="DRAWINGS">FIG. 2</figref>), and <figref idref="DRAWINGS">FIG. 4</figref> is a perspective view of inner band <b>114</b> including an exemplary inner band assembly <b>120</b> that may be used with turbine nozzle <b>104</b>. <figref idref="DRAWINGS">FIG. 5</figref> is a schematic view of turbine nozzle <b>104</b> that may be used with the high-pressure turbine assembly shown in <figref idref="DRAWINGS">FIG. 2</figref>. Turbine nozzle <b>104</b> is one segment of a plurality of segments that are positioned circumferentially about the centerline axis <b>36</b> of rotary machine <b>10</b> to form row <b>102</b> of turbine nozzle <b>104</b> within high-pressure turbine assembly <b>20</b>. In the exemplary embodiment, turbine nozzle <b>104</b> includes an inner band assembly <b>120</b>, an outer band assembly <b>122</b>, and at least one airfoil <b>124</b> coupled to and extending between inner band assembly <b>120</b> and outer band assembly <b>122</b>. More specifically, in one embodiment, inner band assembly <b>120</b> and outer band assembly <b>122</b> are each integrally-formed with airfoil <b>124</b>.

0044Airfoil <b>124</b> includes a pressure-side sidewall <b>126</b> and a suction-side sidewall <b>128</b> that are connected at a leading edge <b>130</b> and at a chordwise-spaced trailing edge <b>132</b> such that sidewalls <b>126</b> and <b>128</b> are defined between edges <b>130</b> and <b>132</b>. Sidewalls <b>126</b> and <b>128</b> each extend radially between inner band assembly <b>120</b> and outer band assembly <b>122</b>. In one embodiment, sidewall <b>126</b> is generally concave and sidewall <b>128</b> is generally convex. Airfoil <b>124</b> also at least partially defines a throat location <b>134</b> proximate trailing edge <b>132</b>. As used herein, the term “throat location” identifies an axial location of the throat between circumferentially adjacent airfoils <b>124</b> in row <b>102</b> of turbine nozzles <b>104</b>. Further, the term “throat” is used herein to indicate the minimum restriction distance between circumferentially adjacent airfoils <b>124</b>. Specifically, the throat is the minimum distance from the pressure-side sidewall <b>126</b>, and more specifically, from the trailing edge <b>132</b> of the pressure-side sidewall <b>126</b> on one airfoil <b>124</b> to the suction-side sidewall <b>128</b> of the adjacent airfoil <b>124</b>. Throat location <b>134</b> occurs where combustion gases <b>118</b> (shown in <figref idref="DRAWINGS">FIG. 2</figref>) have the highest velocity and also represents the location where an area of high static pressure is separated from an area of low static pressure, as described herein.

0045In the exemplary embodiment, outer band assembly <b>122</b> includes a platform portion <b>136</b> coupled to airfoil <b>124</b> and a flange portion <b>138</b> extending radially outward from platform portion <b>136</b>. At least one of platform portion <b>136</b> and flange portion <b>138</b> is coupled to turbine casing <b>116</b>. Similarly, inner band assembly <b>120</b> includes a platform portion <b>140</b>, a first flange <b>142</b>, and a second flange <b>144</b>. As shown in <figref idref="DRAWINGS">FIGS. 3-5</figref>, platform portion <b>140</b> is coupled to airfoil <b>124</b> and extends in a substantially axial direction. Furthermore, first flange <b>142</b> is coupled to platform portion <b>140</b> and is obliquely oriented with respect to centerline axis <b>36</b>. As such, first flange <b>142</b> is also obliquely oriented with respect to platform portion <b>140</b>. Additionally, second flange <b>144</b> is coupled to first flange <b>142</b> such that second flange <b>144</b> is obliquely oriented with respect to first flange <b>142</b> and also extends from first flange <b>142</b> in a substantially radial direction. Specifically, first flange <b>142</b> extends from and is positioned radially inward of platform portion <b>140</b>, and second flange <b>144</b> extends from and is positioned radially inward of first flange <b>142</b>.

0046As shown in <figref idref="DRAWINGS">FIGS. 3-5</figref>, throat location <b>134</b> is positioned proximate trailing edge <b>132</b> of airfoil <b>124</b>. Furthermore, in the exemplary embodiment, platform portion <b>140</b> and first flange <b>142</b> intersect at a point <b>146</b> that is axially aligned with throat location <b>134</b>. First flange <b>142</b> then extends obliquely in both a radial and forward direction to couple with second flange <b>144</b>. In such a configuration, second flange <b>144</b> is axially offset from throat location <b>134</b>. More specifically, second flange <b>144</b> forms a bolted joint with retaining ring <b>110</b> at a location that is axially offset from throat location <b>134</b>. As shown in <figref idref="DRAWINGS">FIG. 5</figref>, throat location <b>134</b> separates a high static pressure area P_SH, forward of throat location <b>134</b>, from a low static pressure area P_SL, aft of throat location <b>134</b>. Furthermore, first flange <b>142</b> separates a nozzle cavity <b>148</b>, forward of first flange <b>142</b> and having a first pressure P₁, from a blade cavity <b>150</b>, aft of first flange <b>142</b> and having a second pressure P₂that is lower than first pressure P₁of nozzle cavity <b>148</b>. Additionally, second pressure P₂is substantially similar to low static pressure area P_SL. In the exemplary embodiment, obliquely oriented first flange <b>142</b> extends nozzle cavity <b>148</b> such that nozzle cavity <b>148</b> terminates at a location substantially axially aligned with throat location <b>134</b> and with intersection point <b>146</b>. Such axial alignment of high static pressure area P_SHand nozzle cavity <b>148</b> at first pressure P₁reduces or prevents purge air from leaking from nozzle cavity <b>148</b> across platform portions <b>140</b> of adjacent turbine nozzles <b>104</b>.

0047In the exemplary embodiment, first flange <b>142</b> includes a first end <b>152</b> coupled to platform portion <b>140</b> and a second end <b>154</b> coupled to second flange <b>144</b>. First flange <b>142</b> also includes a forward surface <b>156</b> extending between first end <b>152</b> and second end <b>154</b> and an aft surface <b>158</b> extending between first end <b>152</b> and second end <b>154</b>. As best shown in <figref idref="DRAWINGS">FIG. 5</figref>, forward surface <b>156</b> and aft surface <b>158</b> are parallel to each other and define a thickness T₁therebetween that is constant between first end <b>152</b> and second end <b>154</b>.

0048In the exemplary embodiment, as best shown in <figref idref="DRAWINGS">FIG. 4</figref>, platform portion <b>140</b> includes a platform seal slot <b>160</b> defined therein and first flange <b>142</b> includes a flange seal slot <b>162</b> defined therein. Platform seal slot <b>160</b> is configured to receive a platform seal member <b>164</b>, and flange seal slot <b>162</b> is configured to receive a flange seal member <b>166</b>. Seal members <b>164</b> and <b>166</b> reduce or prevent purge air in nozzle cavity <b>148</b> from leaking between adjacent turbine nozzles <b>104</b> and intermixing with the hot combustion gases in combustion gas path <b>118</b> (shown in <figref idref="DRAWINGS">FIG. 2</figref>).

0049As shown in <figref idref="DRAWINGS">FIG. 3-5</figref>, similar to first flange <b>142</b> and platform portion <b>140</b>, flange seal slot <b>162</b> is obliquely oriented with respect to platform seal slot <b>160</b>. Additionally, flange seal slot <b>162</b> intersects platform seal slot <b>160</b> at throat location <b>134</b>. In such a configuration, flange seal member <b>166</b> also intersects platform seal member <b>164</b> at throat location <b>134</b>. It is also contemplated that flange seal slot <b>162</b> intersects platform seal slot <b>160</b> forward of throat location <b>134</b> and a second platform seal slot <b>161</b> is formed in platform portion <b>140</b> aftward of platform seal slot <b>160</b> such that no seal slot or seal is present at throat location <b>134</b>, as is shown in <figref idref="DRAWINGS">FIG. 6</figref>.

0050In the embodiment shown in <figref idref="DRAWINGS">FIGS. 3 and 4</figref>, platform seal slot <b>160</b> includes a first end <b>168</b> and an opposing second end <b>170</b>, wherein flange seal slot <b>162</b> extends from second end <b>170</b> and second end <b>170</b> is aligned with throat location. In the embodiment shown in <figref idref="DRAWINGS">FIG. 5</figref>, flange seal slot <b>162</b> and flange seal member <b>166</b> intersect with platform seal slot <b>160</b> and platform seal member <b>164</b> at throat location <b>134</b>, but second end <b>170</b> extends axially aftward beyond throat location <b>134</b> and flange seal slot <b>162</b> and flange seal member <b>166</b>. Furthermore, as shown in <figref idref="DRAWINGS">FIGS. 3-5</figref>, flange seal slot <b>162</b> extends radially into second flange <b>144</b> such that flange seal slot <b>162</b> is at least partially defined in a forward surface <b>172</b> of second flange <b>144</b>, as best shown in <figref idref="DRAWINGS">FIG. 4</figref>.

0051Embodiments of the present disclosure relate to a turbine nozzle for a rotary machine having an angled flange at least partially aligned with a throat of the turbine nozzle. More specifically, the turbine nozzle includes an airfoil that defines a throat location proximate a trailing edge. The turbine nozzle also includes an inner band assembly including a platform portion coupled to the airfoil, and a first flange coupled to the platform portion. The first flange is obliquely oriented with respect to the platform portion, and the platform portion and the first flange intersect at a point axially aligned with the throat location. The inner band assembly also includes a second flange coupled to the first flange such that the second flange is obliquely oriented with respect to the first flange.

0052The design features include positioning an intersection of the platform portion and the first flange at the throat location while also offsetting the second flange from the throat location. Such a configuration may be used in smaller sized rotary machines where spaced for the inner band assembly is limited. Furthermore, the slanted first flange creates a pressurization area inward of the platform portion that maintains a positive backflow margin up to the throat location. More specifically, axial alignment of a high static pressure area and the pressurization area forward of the first flange reduces or prevents purge air from leaking across platform portions of adjacent turbine nozzles and intermixing with the hot combustion gases in the combustion gas path.

0053Exemplary embodiments of a turbine nozzle having an angled flange on the inner band assembly are described above in detail. The turbine nozzle is not limited to the specific embodiments described herein, but rather, components and steps may be utilized independently and separately from other components and/or steps described herein. For example, the embodiments may also be used in combination with other systems and methods, and are not limited to practice with only the gas turbine engine assembly as described herein. Rather, the exemplary embodiment may be implemented and utilized in connection with many other turbine applications.

0054Although specific features of various embodiments of the device may be shown in some drawings and not in others, this is for convenience only. Moreover, references to “one embodiment” in the above description are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. In accordance with the principles of the device, any feature of a drawing may be referenced and/or claimed in combination with any feature of any other drawing.

0055This written description uses examples to disclose the device, including the best mode, and also to enable any person skilled in the art to practice the disclosure, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the device is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.